The invention relates to a card connector assembly having a slot into which cards such as PC cards or the like are inserted. More specifically, the invention relates to a card connector assembly having a slot and an anti-dust shutter that prevents foreign matter from entering the connector.
There has been a rapid increase in the use of PC cards in electronic equipment such as personal computers as a result of the establishment of standards for PC cards such as PCMCIA. PC cards according to PCMCIA standards consist of three types of cards classified according to use, i.e., type I cards are used as semiconductor memory cards, type II cards are used as modem cards, and type III cards are used as hard disk cards. The types of PC cards also have different thickness. Type I and type II cards have almost the same thickness, and type III cards have a thickness that is almost twice that of the type II cards.
Especially in the case of portable personal computers, card connector assemblies are generally equipped with a slot into which PC cards are inserted and a connector that receives the PC cards. Although all three types of cards can be used in common connector assemblies, the method of insertion varies according to the card thickness. Because type I and type II cards have almost the same thickness, these cards can be used in common and each card takes up a single slot. Because type III cards have a thickness that is almost twice that of type II cards, an accommodating space equal to two slots for type II cards is required. Accordingly, so-called double slot type card connector assemblies in which two slots for PCMCIA PC cards are overlapped have been commercialized.
In a double slot type card connector assembly, dirt may enter the interior of the slot or connector and adhere to the connector. Accordingly, an anti-dust shutter is disposed at the card insertion end of the slot and is used to prevent the adhesion of dirt. For example, the mechanism shown in FIG. 15 is known as a conventional anti-dust shutter mechanism for a double slot type card connector assembly (see Japanese Patent Application Laid-Open No. H7-282204). FIG. 15 shows an anti-dust shutter mechanism, a first card slot 101b into which a first card 106 is inserted, and a second card slot 101c into which a second card 107 is inserted. The slots 101b, 101c are disposed in two tiers (above and below) inside an electronic device main body 101. The first and second card slots 101b, 101c open to the outside via a single opening part 101a. A first connector 108 receives the first card 106, and a second connector 109 receives the second card 107. The first and second connectors 108, 109 are disposed in a stacked configuration on the opposite side of the electronic device main body 101 from the opening part 101a. The first card slot 101b and second card slot 101c communicate with each other, so that a third card (not shown) with a thickness that is twice that of the first card 106 or second card 107 can also be inserted. The card connector assembly is arranged so that when the third card is inserted into the first and second card slots 101b, 101c, the third card is connected to the first connector 108.
A first shutter main body 102 is rotatably shaft-supported by a pivoting shaft 102a in the vicinity of the opening part 101a (i.e., in the vicinity of the card insertion end) of the first card slot 101b. A second shutter main body 103 is rotatably shaft-supported by a pivoting shaft 103a in the vicinity of the opening part 101a of the second card slot 101c. The first and second shutter main bodies 102, 103 are disposed like folding doors. When no cards 106, 107 are inserted, the shutter main bodies 102, 103 are spring-driven in the direction that closes the opening part 101a. When the first card 106 and/or second card 107 are inserted, the shutter main bodies 102, 103 are pushed by the cards 106, 107, and pivot so that the shutter main bodies 102, 103 are retracted into the interiors of the first and second card slots 101b, 101c. 
As the first and/or second cards 106, 107 are inserted into the respective first and second card slots 101b, 101c, the first and second shutter main bodies 102, 103 are pushed by the cards 106, 107. The first shutter main body 102 pivots in the direction A, and the second shutter main body 103 pivots in the direction B, as shown in FIG. 15(B). The first shutter main body 102 and second shutter main body 103 retract into the interiors of the first card slot 101b and second card slot 101c. When the first card 106 and second card 107 are pushed in even further, the first card 106 and second card 107 are respectively received in and connected to the first connector 108 and second connector 109. When the first card 106 and second card 107 are respectively connected to the first connector 108 and second connector 109 signals from the respective cards can be transmitted to circuit boards connected to the first connector 108 and second connector 109, or signals from the circuit boards can be conversely transmitted to the respective cards.
Additional PCMCIA standards have been added for cards which handle card busses requiring a ground to be formed on one of the two surfaces of the PC card. FIG. 16 shows a conventional PC card 200 that handles a card bus. The PC card 200 comprises a metal plate part 201 that covers a surface of an insulating housing (not shown), and a metal ground plate part 202 that is disposed on a tip end portion of one surface of the insulating housing. The ground plate part 202 is insulated from the metal plate part 201, and a plurality of protruding contact projections 203 are formed at a specified pitch in the direction of width on the surface of the ground plate part 202. For example, when the PC card 200 is received in the card connector assembly disclosed in Japanese Patent Application Laid-Open No. H8-241764, the contact projections 203 have the function of reducing noise by making contact with ground parts disposed in the card connector assembly.
When the PC card 200 for handling a card bus shown in FIG. 16 is used in the anti-dust shutter mechanism shown in FIG. 15, the contact projections 203 formed on the ground plate part 202 interfere with the free end of the spring-driven first shutter main body 102 or second shutter main body 103 when the PC card 200 is withdrawn from the first card slot 101b or second card slot 101c, as shown in FIG. 17 (FIG. 17 shows only a case in which the PC card 200 is pulled out of the second card slot 101c). Because the contact projections 203 interfere with the free ends of the first and second shutter main bodies 102, 103, the first and second shutter main bodies 102, 103 can be damaged when the PC card 200 is withdrawn.
It is, therefore, desirable to develop a card connector assembly which prevents projections on the surfaces of cards, such as PC cards that handle card busses or the like, from interfering with anti-dust shutters provided on the card connector assembly when the cards are withdrawn from the card connector assembly.
It is an object of the present invention to provide a card connector assembly which makes it possible to prevent raised portions on the surfaces of cards, such as PC cards that handle card busses, from interfering with an anti-dust shutter when the cards are withdrawn from the card connector assembly. This and other objects are achieved by a card connector assembly having a slot for inserting a card that has raised portions and a connector that receives the card that is inserted into the slot. An anti-dust shutter that pivots into an interior of the slot when the card is inserted. The anti dust-shutter having an interference avoiding means in the form of a cut-out or a projection that enables the card to be withdrawn from the slot without interference from the raised portions.